The present invention relates to novel peptides inhibiting phospholipase A.sub.2 (hereinafter referred to as PLA.sub.2) activity.
It has been known that lipocortin is a protein having an amino acid sequence consisting of 346 constituents, a molecular weight of about 37,000 and anti-inflammatory activity, and exhibits an inhibitory activity against PLA.sub.2, an enzyme which induces the formation of inflammation-causing substances [Nature, 320, 77 (1986)]. However, lipocortin is a large molecule protein and is not always suitable for the use in anti-inflammatory drugs in view of the problems such as lack of stability and restriction on administration method.
Further, it has been disclosed that as the amino terminal groups or the carboxyl terminal groups of lipocortin are eliminated, its remaining PLA.sub.2 -inhibiting activity gradually decreases, and a protein having a molecular weight of about 15,000 and which exhibits an inhibitory activity of about 4% of that of lipocortin has been disclosed as the smallest lipocortin fragment having the activity [J. Biol. Chem., 262, 7639 (1987)].